1. Field of the Invention
The present invention provides wheelchair users a more efficient means than has existed heretofore of ingress to and egress from buildings or free standing outdoor or indoor structure, as well of transit between sections of buildings, where said ingress and egress and said transit involve a change in elevation. The invention is centered on a unitary, molded, movable arcuate ramp on which the wheelchair rolls forward or back maintaining a fixed orientation while being raised or lowered, respectively. During the lifting phase, the Accessor moves the wheelchair forward at the same time it lifts it upwards, so as to deliver the wheelchair directly inside or onto the structure to be entered.
2. Description of Prior Art
Several earlier systems going beyond simple fixed ramps have been devised to aid wheelchair-confined persons to traverse changes in vertical position or location. For the most part, these systems have consisted of flat elevator platforms which, while solving the stair by-passing problem, tend to be considerably more cumbersome than the present invention and furthermore do not address the ingress/egress problem concurrently with the raising or lowering of the wheelchair. The prior art which comes closest to the present invention is the "Vehicle Mounted Access Ramp for Wheelchair Users" on which various Letters Patent were issued to Robert H. Royce. That system reversibly lifts and advances a wheelchair into a van interior utilizing a multiple-piece ramp/lift assembly. Royce's invention is strictly limited to use with vans and incorporates several aspects which make it awkward to adapt to use with an enclosed structure or a free-standing stationary structure. Attention is called to U.S. Pat. Nos. 4,155,468, 3,913,759, 3,874,527, 3,711,882, 3,411,169, and 1,034,061.